Shared Roster changing JID's to lower case

My users have names like "Jabber.User@im.local"

I use LDAP+Active Directory to log them in and that works fine.

I have a shared roster. When I save the roster, the user names are converted to lower case.
It looks like the JID of the user is compared in lower case to the JID's in the roster, so the roster is sent, but I don't want the names in the roster to be all lower case, I want them to be as entered.

Is this a configurable option?